One example of conventional semiconductor devices is disclosed in Patent Literature 1. The semiconductor device (optical semiconductor device) described in Patent literature 1 includes a metallic lead frame, a semiconductor element (optical semiconductor element) bonded to a front surface of the lead frame, and a resin member (light reflective resin, light translucent resin) that covers the lead frame and the semiconductor element.
A large number of lead frames are acquired from one metallic board of a flat plate shape, and in an initial manufacturing stage, the lead frames are coupled to each other via a coupling portion. The lead frames each have a plurality of recesses formed in its front surface. The recesses are formed in an area other than an area near the coupling portion so as not to be formed in the area near the coupling portion. As describe above, the semiconductor element and the resin member are formed on each of the lead frames and then the coupling portion is cut. Thus, the individual semiconductor devices are manufactured.
According to Patent Literature 1, the resin member enters the recesses to enhance adhesion of the resin member to the lead frame. Since the recesses are not formed in the area near the coupling portion, the thickness of the lead frame near the coupling portion can be kept larger than the thickness of the area where the recesses are formed, preventing plastic deformation of the lead frame due to a stress caused by cutting the coupling portion.